1. Field of the Invention
The present invention relates to an oil drain technique, and more particularly to an oil drain connector able to release pressure and to present the liquid from leaking.
2. Description of the Prior Art
In a conventional seal container, such as a water filter or an oil-water separator, when the liquid (such as oil) inside the container reaches a certain level, the liquid must be drained to prevent the efficiency of the water filter or the oil-water separator from being lowered.
For draining the oil, the bottom of the container is provided with a liquid drain device. The liquid drain device is detachably connected to the bottom of the container. The liquid drain device has a liquid channel. When it is required to drain the liquid, the liquid drain device is loosened relative to the bottom of the container for the air to enter the container from the gap between the liquid drain device and the container. At the same time, the liquid inside the container is drained from the liquid channel.
However, because the pressure inside the container is larger than the pressure (atmospheric pressure) out of the container, the liquid inside the container may leak from the gap between the liquid drain device and the container to wet other positions. It is very inconvenient for use.
Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve this problem.